Writing in the Journal of Agricultural and Food Chemistry, the scientists report that Korean pine nut oil was also associated with changes in the expression of certain proteins, which produced metabolic benefits for the lab animals used in the study.
“[These metabolic changes] lead to a reduction in muscle lipid content and body weight gain,” wrote the researchers from the University of Ulsan and Seoul National University in South Korea, and Kyoto University in Japan.
“Pine nut oil may have potential as a dietary supplement for preventing obesity and metabolic dysregulation in skeletal muscle and [brown fat tissue].”
The potential weight management potential of Korean pine nut oil is not new, with Stepan offering the Pinnothin-branded ingredient (formerly Lipid Nutrition). This ingredient, containing the polyunsaturated fatty acid pinolenic acid derived from the seeds of the Korean pine nut tree (Pinus koraiensis) is reported to boost expression of the appetite-suppressing hormones (glucagon-like peptide-1) GLP-1 and cholecystokinin (CCK). The hormones are reported to work by delaying the emptying of the stomach (gastric emptying) and thereby promoting the feeling of fullness.
Indeed, a peer-reviewed study was published in the BioMed Central journal Lipids in Health and Disease in 2008 (7:6 doi:10.1186/1476-511X-7-6), which found the ingredient may also help reduce food consumption. Researchers from the University of Liverpool reported that at a dose of 2 grams free fatty acids (FFA) the ingredient was associated with a 9 percent reduction in food intake.
The researchers behind the new study note that, while studies have shown that pine nut oil may have beneficial effects on some measure of metabolism, levels of triglyceride and cholesterol, and atherogenesis in lab animals, it is “not known whether pine nut oil can improve the dysregulated lipid metabolism accompanied by impaired mitochondrial function frequently observed in obese individuals”.
The researchers fed lab mice a high fat diet with supplemental pine nut oil or soybean oil for 12 weeks at levels of 10 or 30% of the total energy intake.
Results showed that the pine nut oil fed animals gained less weight and had lower fat build up in their muscles, compared with the soybean-fed animals.
In addition, the pine nut oil was associated with an upregulation of proteins linked to oxidative metabolism and to the activity of AMP-activated protein kinase (AMPK), said to be the master regulator of in metabolic pathways involved in glucose and fatty acid metabolism.
The pine nut oil was also associated with selective expression of genes for muscle fibers.
Commenting on the potential mechanism, the researchers note the beneficial metabolic effects were, in part, linked to the ability of pinolenic acid to bind to different types of receptors in cells to switch on these processes.
“Our findings suggest that pine nut oil may have potential as a dietary supplement for counteracting obesity and metabolic dysregulation,” the concluded.
Commenting on the new study, Emile Henein, global business manager for Stepan Lipid Nutrition, told us that the major difference between the ingredient used in this study and Stepan’s PinnoThin ingredient is that the majority of the PinnoThin work was done in humans.
“Our in vitro studies with pine nut oil were limited to in vitro hormone release assays. Another difference is that we only did single dose studies, whereas in the publication dosing was continued for weeks. Our efforts were in place to measure the release of hormones related to satiety.”
“An aspect that is currently missing from the current study is the link with humans,” he added.
“How much pine nut oil should someone take to get 25 or 50 uM of pinoleic acid in his or her blood? Such levels can be reached after dosing CLA at 3 grams per person, but pine nut oil only contains about 15% pinoleic acid. This means that Pine nut oils should roughly be dosed at 18 grams per day to be effective. Such levels are probably unattainable.
“We would have liked to see a discussion on the relevance of this finding on pinoleic acid for humans.
“Another observation in this study, is missing data on subcuteneous fat-mass and lean body mass of course. Since the pine nut oil animals lost some weight and AMPK was activated, we would expect that fat mass would decrease and lean body mass would increase. Perhaps this will be addressed in their next publication."
PinnoThin in the marketplace
Heinen added that the area of ingredients that promote satiety is a most challenging scientific area, and even more challenging to translate these results into the market.
“At the retail level, we are noticing short product life cycles for products containing PinnoThin - but also for comparative ingredients with similar science referencing satiety due to releases of specific hormones.
“Nevertheless, brand managers across the world continue to be interested in PinnoThin, and often consider it in combination with other ingredients for re-launches.
He added that they have heard reports of similar observations for competing ingredients in the satiety claims.
Source: Journal of Agricultural and Food Chemistry
Published online ahead of print, doi: 10.1021/jf303548k
“Diet Enriched with Korean Pine Nut Oil Improves Mitochondrial Oxidative Metabolism in Skeletal Muscle and Brown Adipose Tissue in Diet-Induced Obesity”
Authors: N.H. Le, S. Shin, T.H. Tu, et al.